This invention relates generally to vehicle inflatable occupant restraints and, more particularly, to the attachment of a cover door for an opening in a vehicle panel which mounts an inflatable air bag for deployment rearwardly of the panel.
Inflatable occupant restraint systems for passengers of vehicles conventionally comprise a restraint module which houses an inflatable air bag and an inflator. This module is mounted in the steering wheel hub for driver use and in a recess in the instrument panel for front seat passenger use.
The instrument panel opening is conventionally closed by a cover door that can take several forms. In one, a vertical door hinged about its lower edge to the instrument panel opens downwardly to enable deployment of the inflating bag. In another, a vertical door arrangement includes door halves which open upwardly and downwardly to enable bag deployment.
Cover doors often feature a rectangular portion of the instrument panel padded cover having weakened sections or stitching segments about three sides which are fractured by the inflating air bag to create a door which hinges about the other side to open. Such arrangements have the disadvantage of requiring replacement of the vehicle instrument panel should the bag deploy in circumstances enabling reuse of the vehicle. The location of these restraint mountings on the vertical face of the instrument panel also suffer the disadvantage of necessitating removal or repositioning of the conventional glove box.
Other restraint mounting arrangements have been developed to locate the restraint module subjacent an opening in the upper surface of the instrument panel. This location eliminates interference with the glove box. U.S. Pat. No. 3,944,250 and German Patent Application DE 3843-686-A both illustrate such a mounting which utilizes a separate, separable door that releases upon bag inflation to occupy a position against the vehicle windshield. The door forward edge is held in this position by a tether. It is known to utilize a woven fabric material which is molded into the foam and substrate laminate of the door to form this tether.
Another upper panel mounting is illustrated in U.S. Pat. No. 4,911,471 which provides a door integral with the instrument panel. Upon deployment of the inflating bag, a weakened section of the instrument panel fractures about three sides to form a door which hinges about its front edge to open. A pair of side tethers are utilized to limit opening movement of the door to prevent its rear edge from striking the vehicle windshield.
It is desirable in any installation of an inflatable restraint to provide for rapid and accurate deployment of the inflating air bag through an opening in a vehicle panel, while concealing the air bag from view. This requires a cover door mounting arrangement which enables the door to open or be removed while either assisting or not hindering deployment of the inflating bag.
It is desirable to provide a separate closure door for an opening in a vehicle panel having a subjacently mounted inflatable restraint which is separable to a predetermined position to facilitate inflating bag deployment.